reducing latency for live performance.

I would like to use live...well, live.  How can I reduce latency to the very least possible.

I am a drummer and piano player, two instruments where even just a few milliseconds of latency can throw me off.

I would like to run live instruments (such as a guitar) through live and its effects, then out to a PA system. For example, run a guitar into live and through its AMP effect. 

Or run the AUDIO from my digital drum set through  a live channel hosting an EQ, distortion, freq delay, etc... then out to my speakers. But I need latency to be reduced

as much as my system can reduce it.